Moving away from GPS to a Multi-Sensor, Inertial-Centered Architecture

Advanced Navigation announced a hybrid solution for long endurance GNSS-denied navigation. The system does not rely on GPS, but rather a combination of INS and laser-based velocity aid. Held together by intelligent software, the solution can dynamically weigh the input from each sensor, adjusting in real time based on reliability scores, environmental conditions, and operational context. This ensures continuous, high-confidence state estimation even when signals are lost, degraded, or distorted.

The limitations of GPS

Vulnerabilities including spoofing and jamming attacks, harsh environments and extreme makes it clear that while GPS will remain a cornerstone of modern infrastructure, it can no longer be treated it as a single source of truth. To protect critical systems and future-proof our operations, a transition from GPS-only to a multi-sensor, inertial-centered architecture is necessary. The Hybrid Navigation System is built with this purpose in mind. 

The new Hybrid Navigation System is purpose-built for GPS-denied and contested environments. 

“GPS-denied” refers to any scenario or environment where GPS signals drop out, become inconsistent or unreliable, or completely fail to work. Able to operate effectively on both ground and airborne platforms provided it has a clear line of sight to the ground or another stationary surface, the Hybrid Navigation System has applications for a wide range of GPS-denied environments, with indoor being one of them.

LVS Development background

LVS is a terrestrial adaptation of LUNA, a space-grade navigation technology originally developed for autonomous lunar landings. LUNA enables reliable navigation in the harsh environment of space by providing precise 3D velocity and altitude information relative to the Moon’s surface. 

As there is a greater need for easier engagement with the cosmic frontier to deploy satellites, build space stations, and land scientific equipment on the Moon, LUNA’s development is driven by the increasing commercialization that comes with more frequent lunar explorations. The result of several years of R&D, LUNA is set to be demonstrated aboard Intuitive Machines’ Nova-C lander as part of NASA’s Commercial Lunar Payload Services (CLPS) program.

In 2024, Advanced Navigation received a $1m AUD grant by the Australian federal government. The grant helped the team to accelerate the development of the technology for terrestrial applications. By leveraging the engineering insights gained from LUNA, LVS transforms space technology into an Earth-ready solution for GNSS-denied navigation. 

LVS hybrid architecture components

The terrestrial adaptation of LUNA fuses a strategic-grade Inertial Navigation System (INS) with a proprietary Laser Velocity Sensor (LVS). An INS uses a computer, motion sensors (accelerometers) and rotation sensors (gyroscopes) to continuously calculate by dead-reckoning the position, the orientation, and the velocity of a moving object without the need for external references such as GNSS/GPS. LVS uses infrared lasers to measure a vehicle’s ground-relative 3D velocity with accuracy and precision.

An INS typically relies on MEMS-based accelerometers and gyroscopes, which introduce significant drift over time. While Fiber-Optic Gyroscope (FOG) -based INS offers superior stability compared to MEMS devices, accurate velocity aiding is essential for maintaining long-term navigation accuracy. 

However, conventional velocity aiding methods come with limitations. For example, Visual-Inertial Odometry (VIO), which uses cameras and Inertial Measurement Unit (IMU) data to estimate motion through feature tracking, is effective in structured environments but struggles against unreliable visual references and poor lighting conditions. While wheel-speed sensors, which measure the forward velocity for ground vehicles, require continuous ground contact and are subject to wheel slip.

Unlike conventional velocity sensors, LVS operates effectively on both ground and airborne platforms, provided it has a clear line of sight to the ground or another stationary surface. Beyond its role as a velocity aid, LVS also enhances navigation resilience by detecting GNSS spoofing. By comparing its independent velocity measurements against GNSS-derived velocity, LVS adds an extra layer of security to Assured Positioning, Navigation and Timing (APNT) strategies. When integrated with an INS, such as Advanced Navigation’s high-end commercial FOG, the Boreas D90, LVS can provide direct, drift-free velocity measurements, ensuring continuous, high-precision mobility for vehicles in GNSS-denied environments. 

The below image shows configuration of the Boreas D90 FOG INS integrated with LVS in the front of the Tesla Model Y used for ground vehicle testing. The LVS Sensor Head uses three lasers, labelled A, B, and C, to measure the vehicle's ground-relative 3D velocity.

The Hybrid Navigation System will be commercially available later this year. It’s developed to be dual use for the widespread adoption across critical defense, aerospace, robotics and autonomous system sectors.